Burglar-alarm.



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PATENTED APR. 18. 1905.

1 M WW 1 A DMm AAH .LN A RT mm L Patented April 18, 1905.

UNTTED STATES PATENT EEicE.

ALFRED A. DAY, OF BROUKTON, MASSAUIIUSET"S.

BURGLAR-ALARIVI.

SPECIFICATION forming part of Letters Patent No. 787,358, dated April18, 1905.

Application filed February 25,1904. Serial No. 195,211.

be it known that I, ALFRED A. DAY, a citizen of the United States,residing at Broekton, in the county of Plymouth and State ofMassachusetts, have invented new and useful linprovements inBurglar-Alarms, of which the following is a specification.

My invention relates to improvements in burglar-alarms of the detonatingtype, and has for its object to provide a novel, simple, and inexpensivebu rglar-alarm which will ex pose an attempt to gain entrance to awindow or door to which it is applied.

\Yith this object in view myinvention consists in a burglar-alarmconstructed as hereinafter described and claimed, reference being had tothe accompanying drawings, in which Figure l is a perspective viewthereof as applied to a window. Fig. 2 is a perspective view ofthehammer element. Fig. 3 is a perspective view of the trigger element, andFig. i is a plan view looking down on the burglaralarm as applied to awindow.

lremising that the alarm may be connected with a door or other entranceinto a house by properly positioning the parts for such change ofrelation, the reference-mnneral1 designates generally the hammer elementof the alarm, which is secured to awindow-frame in any suitable way, asby screws. This element consists of a single pieceof material fashionedat one end to form a detonating-cap support Adjacent this support thematerial is shaped to provide eyes w to receive screws or similarfastening means. It is then bent to form lateral arms T, connected by ahammer guide-bar T. which incloses the space in which the hammer movesand guides the latter in its movement. form an eye w to receive afastening device, after which it is again bent upon itself laterallytoward the guide-bar T to provide a liammer-support :2, dished to form ahammerseat I and a hammer-keeper It is then tached for use.

The material is then shaped to l is provided to receive a fasteningdevice, l and the material is then coiled to form a spring s, from whichcoil it extends in a free arm constituting a spring-hammer 8, adapted toinitially rest in the seat 3 of the support 2 and be tripped and movedoti'of said support and partake of a guided swinging movement to thecap-support and explode the cap to sound an alarm. The end 9 of saidhammer projects into the path of the trigger, next referred to. i Thetrigger element 10 is suitably secured to the part to which it isconnected by means of screws, as shown. This trigger element is inclineddownwardly and at an acute angle, and thus it has a compound incline, asshown l in the (lra\\"ings. It is inclined away from the part to whichit is attached. whereby the hammer, which when released moves in the arcof a circle, may swing without coming in contact with the part to whichthe trigger element is connected, avoiding the necessity of providing arecess for the passage of said hammer in its swinging movements. inother words, this incline ol the trigger element reaches out toward thehammer. It is also provided with an incline at substantially rightangles to that just described, so that it will engage the hammer to liftit from its seat 3 and off over the keeper, whereupon, by reason of thefact that the hammer is a springhammer, it will pass forcefully to andagainst and explode the detonating-cap, being guided or directed in thismovement by means of the guide 7.

The burglar-alarm of my invention in the form illustrated in thedrawings is constructed of wire, the keeper and hammer element beingmade of one integral piece of wire, as shown, and the trigger element ofanother single piece of wire. This results in great simplicity andeconomy of construction. \Vhen constructed of a singlepiece of wire, thetriggel-element is seen red atone end conveniently by a screw, is theninclined downwardly at an acute angle, as shown at 10, Fig. 3, then isbent at a right angle to form the arm 11. It is then bent toward thepoint to which it is secured, as shown at 12, whereby the two points ofattachment are in alinement, imparting rigidity and allowing the hammerto ride off freely.

While I have shown the trigger as applied to the moving part of anentrance to a house and the keeper and hammer element to the stationarypart, it is obvious that the positions of these elements may be reversedor inter: changed.

Having thus described my invention, What I claim is A burglar-alarmcomprising a hammer element consisting of a single piece of materialformed With eyes to receive attaching devices, fashioned at one end toprovide a cap-support, having laterally-bent arms connected by a hammerguide-bar, bent laterally to form a dished hammer-support, coiled toprovide a spring, and terminating in afree arm constituting aspring-hammer the end of which projects into the path of the trigger;and a trigger element provided with an incline to engage and release thehammer from its support, substantially as described.

In testimony whereof I have hereunto set my hand in presence of twosubscribing Witnesses.

ALFRED A. DAY.

Witnesses:

E. E. GOODWIN, ARTHUR L. RICH.

